An increased risk of epithelial ovarian cancer in Taiwanese women with a new surgico-pathological diagnosis of endometriosis

Table 1 Baseline characteristics of the study subjects

	Total (n = 29725)		Endometriosis patients (n = 5945)		Controls (n = 23780)		P-value
Person-years	168927		33519		135408
Variable	n	%	n	%	n	%
Catastrophic illness							< 0.0001
EOC	75	0.25	39	0.66	36	0.15
No EOC	29650	99.75	5906	99.34	23744	99.85
Age*							0.0750
≤ 41	14877	50.05	2914	49.02	11963	50.31
e> 41	14848	49.95	3031	50.98	11817	49.69
SES							0.8868
≥ 40000	4579	15.40	911	15.32	3668	15.42
20000-39999	9790	32.94	1941	32.65	7849	33.01
< 20000	10236	34.44	2073	34.87	8163	34.33
Others	5120	17.22	1020	17.16	4100	17.24
Work							0.5954
Yes	27617	92.91	5514	92.75	22103	92.95
No	2108	7.09	431	7.25	1677	7.05
Urbanization							0.9752
Urban	9957	33.50	1991	33.49	7966	33.50
Suburban	12549	42.22	2504	42.12	10045	42.24
Rural	7219	24.29	1450	24.39	5769	24.26
PID							< 0.0001
Yes	13647	45.91	4518	76.00	9129	38.39
No	16078	54.09	1427	24.00	14651	61.61
Infertility							< 0.0001
Yes	1094	3.68	608	10.23	486	2.04
No	28631	96.32	5337	89.77	23294	97.96
CV disease							< 0.0001
Yes	1133	3.81	290	4.88	843	3.54
No	28592	96.19	5655	95.12	22937	96.46
Diabetes mellitus							< 0.0001
Yes	1820	6.12	448	7.54	1372	5.77
No	27905	93.88	5497	92.46	22408	94.23
Chronic liver disease							0.0002
Yes	477	1.60	128	2.15	349	1.47
No	29248	98.40	5817	97.85	23431	98.53
Rheumatic disease							< 0.0001
Yes	796	2.68	235	3.95	561	2.36
No	28929	97.32	5710	96.05	23219	97.64

EOC: invasive epithelial ovarian cancer; SES: socio-economic status; PID: pelvic inflammatory disease; CV disease: cardiovascular disease.
*Age variable was matched by the exact year of age, but the table shows age quartile groups. The median age of women with and without endometriosis was 40.5 and 40.4 years of age, respectively (p = 0.3570).

ISSN: 1471-2407